Interference of oral phenytoin absorption by continuous nasogastric feedings.
Inhibition of phenytoin absorption by continuous nasogastric tube feeding was studied in 20 neurosurgery patients and 5 normal subjects. Ten patients receiving phenytoin suspension 300 mg per day coadministered with continuous nasogastric feedings had a mean phenytoin serum concentration of 2.59 micrograms per milliliter. When the feedings were discontinued, the average concentration rose to 10.22 micrograms per milliliter in 7 days. In 10 other patients stabilized on phenytoin suspension 300 mg per day, the average serum concentration decreased from 9.80 microgram per milliliter to 2.72 microgram per milliliter in 7 days when continuous tube feedings were started. Five normal subjects received a single oral dose of phenytoin suspension alone and while drinking a nasogastric tube feeding preparation orally at a rate of 100 ml per hour; phenytoin serum levels decreased an average of 71.6% when the tube feeding was taken concurrently.
D000328:Adult; D005260:Female; D006801:Humans; D007441:Intubation, Gastrointestinal / Q000009:adverse effects*; D008297:Male; D010288:Parenteral Nutrition / Q000009:adverse effects*; D010672:Phenytoin / Q000008:administration & dosage / Q000097:blood / Q000378:metabolism*; D012640:Seizures / Q000188:drug therapy
D010672:Phenytoin